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                                                                   Exhibit 10(b)

                    THIRD AMENDMENT TO AMENDED AND RESTATED
                    ---------------------------------------
                          LOAN AND SECURITY AGREEMENT
                          ---------------------------


     This Third Amendment to Amended and Restated Loan and Security Agreement
(this "Amendment") is made this 31st day of October 2000 by and among Berger
Financial Corp. ("BFC"), a Delaware corporation, Berger Bros Company ("BBC"), a
Pennsylvania corporation and Berger Holdings, Ltd. ("BHL"), a Pennsylvania
corporation, each with its chief executive office at 805 Pennsylvania Boulevard,
Feasterville, Pennsylvania 19053, CopperCraft, Inc. ("CCI"), a Texas corporation
having its chief executive office at 4995 Keller Haslet Road, Keller, Texas
76244, Walker Metal Products, Inc. ("Walker"), a Georgia corporation having its
chief executive office at 1210 Dalton Road NE, Atlanta, Georgia 30306, and
Summit Bank ("Bank"), a New Jersey bank having offices at 4900 Route 70,
Pennsauken, New Jersey 08109-4792. BFC, BBC, CCI and Walker are hereinafter
collectively referred to and jointly and severally obligated as "Borrower."
Borrower and BHL are hereinafter collectively referred to and jointly and
severally obligated as "Obligors."

                                  BACKGROUND
                                  ----------

     A.   Pursuant to the terms and subject to the conditions set forth in that
certain Amended and Restated Loan and Security Agreement dated January 2, 1998
between Borrower and Bank, as amended pursuant to the terms and subject to the
conditions set forth in that certain Amendment to Amended and Restated Loan and
Security Agreement dated December 7, 1998 between Borrower and Bank, that
certain Second Amendment to Amended and Restated Loan and Security Agreement
(the "Second Amendment") dated December 20, 1999 between Obligors and Bank, that
certain letter amendment dated January 20, 2000 among Obligors (other than CCI)
and Bank, that certain letter agreement dated February 28, 2000 among Obligors
(other than CCI) and Bank, that certain Joinder and Assumption Agreement dated
March 31, 2000 among Obligors and Bank, pursuant to which CCI joined, assumed in
the Financing Agreements and agreed to be liable for the Obligations, and that
certain Joinder and Assumption Agreement of even date herewith pursuant to which
Walker joined in the Financing Agreements, assumed and agreed to be liable for
the Obligations (as amended, the "Loan Agreement"), and related instruments,
agreements and documents including, without limitation, the Surety Agreement
(collectively, along with the Loan Agreement, the "Financing Agreements"),
Obligors are currently indebted to Bank for repayment of (i) various loans,
advances and extensions of credit made pursuant to a revolving credit facility
made available by Bank to Borrower in a principal sum of up to Seventeen Million
Five Hundred Thousand ($17,500,000.00) Dollars (the "Revolving Credit"), which
indebtedness is further evidenced by that certain Second Replacement Revolving
Credit Note dated December 20, 1999 in the principal sum of Seventeen Million
Five Hundred Thousand ($17,500,000.00) Dollars executed and delivered by
Borrower to Bank (the "Revolving Credit Note"); (ii) a term loan made by Bank to
Borrower in the principal sum of Two Million Four Hundred Thousand
($2,400,000.00) Dollars (the "Term Loan"), which indebtedness is further
evidenced by that certain Second Replacement Term Loan Note dated December 20,
1999 in the principal sum of One Million Eight Hundred Sixty-Eight Thousand and
Four ($1,868,004.00) Dollars executed and delivered by Borrower to Bank (the
<PAGE>

"Term Loan Note"), and (iii) a supplemental term loan made by Bank to Borrower
in the principal sum of Two Million ($2,000,000.00) Dollars (the "Supplemental
Term Loan"), which indebtedness is further evidenced by that certain
Supplemental Term Loan Note dated December 20, 1999 in the principal sum of Two
Million ($2,000,000.00) Dollars executed and delivered by Borrower to Bank (the
"Supplemental Term Loan Note") and (iv) an acquisition line loan made by Bank to
Borrower in the principal sum of One Hundred Sixty-Four Thousand Seven Hundred
Thirty-Five ($164,735.00) Dollars (the "Acquisition Line Loan"), which
indebtedness is evidenced by that certain Acquisition Line Term Loan Note dated
March 31, 2000 in the principal sum of One Hundred Sixty-Four Thousand Seven
Hundred Thirty-Five ($164,735.00) Dollars executed and delivered by Borrower to
Bank (the "Acquisition Line Term Loan Note"). The Revolving Credit Note, the
Term Loan Note, the Supplemental Term Loan Note and the Acquisition Line Term
Loan Note are hereinafter collectively referred to as the "Notes."

     B.   To induce Bank to enter into the Financing Agreements, pursuant to the
terms and subject to the conditions set forth in certain Amended and Restated
Surety Agreement dated January 2, 1998 executed and delivered by BHL to Bank
(the "Surety Agreement"), BHL guaranteed, as a surety, all existing and future
debts, liabilities and obligations of Borrower to Bank including, without
limitation, the debts, liabilities and obligations evidenced by the Existing
Notes. To secure BHL's indebtedness to Bank as a surety for the debts,
liabilities and obligations of Borrower to Bank, pursuant to a certain Security
Agreement dated August 21, 1997 between BHL and Bank, BHL granted Bank
continuing liens on and security interests in and to all of BHL's existing and
future accounts, chattel paper, contracts, documents, equipment, fixtures,
general intangibles, goods, instruments, inventory, investment property and the
cash and non-cash proceeds thereof, all as more fully described in such Security
Agreement.

     C.   All capitalized terms not otherwise defined in this Amendment shall
have the meanings ascribed to such terms in the Loan Agreement.

     D.   Borrower has requested that Bank, among other things, (i) decrease the
Maximum Line Amount to Fifteen Million ($15,000,000.00) Dollars, (ii) modify
certain financial covenants set forth in the Loan Agreement and (iii) make a
Loan under the Acquisition Line Facility, and Bank is willing to accommodate
Borrower in accordance with such requests for modifications to the Financing
Agreements in accordance with the terms and subject to the conditions set forth
in this Amendment and in the instruments, agreements and documents referred to
in this Amendment.

     NOW, THEREFORE, with the foregoing background deemed incorporated
hereinafter by this reference and hereby made a part hereof, the parties hereto,
intending to be legally bound hereby, further covenant and agree as follows:

     1.   Confirmation of Existing Indebtedness. Obligors hereby unconditionally
          -------------------------------------
acknowledge and confirm that: (a) the unpaid principal indebtedness of Borrower
to Bank evidenced by the Revolving Credit Note is, as of October 31, 2000, Six
Million Eight Hundred Thirty Thousand Four Hundred Thirty-Eight and 10/100
($6,830,438.10) Dollars; (b) interest on the outstanding principal balance of
the Revolving Credit has been paid through September 30,

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2000; (c) the unpaid principal indebtedness of Borrower to Bank evidenced by the
Term Loan Note is, as of the date hereof, One Million Four Hundred Twenty-Four
Thousand Six Hundred Seventy-Four ($1,424,674.00) Dollars; (d) interest on the
outstanding principal balance of the Term Loan has been paid through September
30, 2000; (e) the unpaid principal indebtedness of Borrower to Bank evidenced by
the Supplemental Term Loan is, as of the date hereof, One Million Five Hundred
Seventy-Five Thousand Eight Hundred ($1,575,800.00) Dollars; (f) interest on the
outstanding principal balance of the Supplemental Term Loan Note as in paid
through September 30, 2000; (g) the unpaid principal indebtedness of Borrower to
Bank evidenced by the Acquisition Line Term Loan Note is, as of the date hereof,
One Hundred Forty-Eight Thousand Two Hundred Sixty-One and 52/100 ($148,261.52)
Dollars; (h) interest on the outstanding principal balance of the Acquisition
Line Term Loan Note as been paid through September 30, 2000; and (i) the
foregoing sums, together with continually accruing interest and any related
costs, fees and expenses are, as of the date hereof, owing without claim,
counterclaim, right of recoupment, defense or set off of any kind or of any
nature whatsoever.

     2.   Ratification of Financing Agreements. Obligors hereby ratify, confirm
          ------------------------------------
and reaffirm in all respects and without condition, all of the terms, covenants
and conditions set forth in the Financing Agreements, and hereby agree that each
of them remain unconditionally liable to Bank in accordance with the respective
terms, covenants and conditions of such instruments, agreements and documents,
and that all Collateral, liens, security interests and pledges created pursuant
thereto and/or referred to therein continue unimpaired and in full force and
effect, and secure and shall continue to secure all of the Obligations.

     3.   Warranties and Representations.
          ------------------------------

          (a)  Except as qualified on Schedule 3(a) attached hereto and
incorporated herein by this reference, all warranties and representations set
forth in the Loan Agreement and the Surety Agreement are hereby respectively
asserted, reasserted, stated and restated by Borrower and BHL (as applicable) as
of the date hereof as if the same were set forth at length herein. Obligors
acknowledge that such warranties and representations (and the warranties and
representations set forth herein) are being specifically relied upon by Bank as
a material inducement to Bank to enter into this Amendment.

          (b)  As a further inducement to Bank to enter into this Amendment,
Obligors further represent and warrant to Bank that:

               (i)  Each Obligor has the power, authority and capacity to enter
into and perform this Amendment and all related instruments, agreements and
documents, and to incur the Obligations herein and therein provided for, and
such Obligor has taken all proper and necessary corporate action to authorize
the execution, delivery and performance of this Amendment and related
instruments, agreements and documents;

               (ii) This Amendment is, and the Third Replacement Revolving
Credit Note and the Second Acquisition Line Term Loan Note (each as hereinafter
defined) and the

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other Financing Agreements, when executed and delivered by Borrower will be
valid, binding and enforceable against each Obligor in accordance with their
respective terms;

               (iii)  No consent, approval or authorization of, or filing,
registration or qualification with, any Person (including any holder of
Subordinated Indebtedness or of liens on Collateral) is required to be obtained
by any Obligor in connection with the execution and delivery of this Amendment
and the instruments, agreements and documents referred to in this Amendment; and

               (iv)   No Event of Default or Potential Default has occurred
under the Financing Agreements.

     4.   Amendments to Loan Agreement.  Under the terms and subject to the
          ----------------------------
conditions set forth in this Amendment, the Loan Agreement and the other
Financing Agreements are hereby amended as follows:

          (a)  Paragraph 1.5 of the Loan Agreement is hereby amended and
restated to read in its entirety as follows:

               1.5  "Borrowing Base" means, at any time, an amount shown on the
               most current Borrowing Base Certificate executed and delivered by
               Borrower to Bank equal to the lesser of:

                    1.5.1  Fifteen Million ($15,000,000.00) Dollars ("Maximum
               Line Amount"); or

                    1.5.2  An amount up to the sum of (a) eighty-five (85%)
               percent of the net outstanding amount of Eligible Accounts, after
               deducting therefrom all payments, adjustments and credits
               applicable thereto, and (b) the lesser of (i) fifty (50%) percent
               of the value (determined on the basis of the lower of cost or
               market value) of Eligible Inventory and (ii) Four Million Five
               Hundred Thousand ($4,500,000.00) Dollars. The foregoing
               percentage advance rates are subject to periodic examination and
               analysis by Bank and, as a result thereof, and in Bank's
               discretion exercised reasonably and in good faith, are subject to
               change.

          (b)  Paragraph 1.29 of the Loan Agreement is hereby amended to include
within the definition of "Notes" any Instruments evidencing Obligations
including, without limitation, the Third Replacement Revolving Credit Note, the
Second Acquisition Line Term Loan Note and any instruments, agreements and
documents executed and/or delivered in replacement or substitution or
modification thereof.

          (c)  The term "Revolving Credit" as used in the Loan Agreement shall
hereafter refer to the Revolving Credit as reduced pursuant to the terms and
subject to the conditions of this Amendment.

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          (d)  Notwithstanding anything to the contrary set forth in Paragraph
2.4 of the Loan Agreement, and in addition to the Permitted Acquisition Line
Overadvances described at Paragraph 6 of the Second Amendment, so long as there
has occurred no Event of Default or any Potential Default which is continuing,
for the period from December 1, 2000 through and including May 31, 2001, the
Revolving Credit may include loans, advances and extensions of credit in excess
of the Borrowing Base (collectively, the "Permitted Overadvances") in an
aggregate amount of up to Five Hundred Thousand ($500,000.00) Dollars; provided,
                                                                       --------
however, at no time shall the amount outstanding under the Revolving Credit
-------
exceed the Maximum Line Amount. If at any time the Permitted Overadvances shall,
for any reason, exceed Five Hundred Thousand ($500,000.00) Dollars, Borrower
shall immediately repay to Bank such amount as may be necessary to eliminate
such excess, and on June 1, 2000, no Permitted Overadvances shall be
outstanding.

          (e)  Subparagraph 5(a)(iii)(3) of the Second Amendment, which
amendment has been incorporated by reference into and made a part of the Loan
Agreement, is hereby amended to provide that Obligors (including Walker and any
future Target acquired) shall have and maintain a ratio of Consolidated Senior
Liabilities (defined to be all Liabilities minus the long-term portion of
Subordinated Indebtedness) to Tangible Net Worth of less than: 4.40 to 1.00 from
October 31, 2000 through and including March 31, 2001; 4.00 to 1.00 from April
1, 2001 through and including June 30, 2001; 3.50 to 1.00 from July 1, 2001
through and including September 30, 2001; and 3.00 to 1.00 at all times
thereafter.

     5.   Second Acquisition Line Loan; Second Acquisition Line Term Loan Note.
          --------------------------------------------------------------------
Subject to satisfaction of all conditions proceed and set forth in this
Amendment and in the Loan Agreement, Bank shall, under the terms and subject to
the conditions set forth in the Financing Agreements, make a second Acquisition
Line Loan advance in the principal sum of Three Hundred Eighty-Four Thousand
Four Hundred Eighty-Eight ($384,488.00) Dollars (the "Second Acquisition Line
Loan").  To evidence Borrower's obligations to repay Bank, with interest,
Borrower shall execute and deliver to Bank its promissory note (the "Second
Acquisition Line Term Note") in the principal sum of the Second Acquisition Line
Loan, all as more fully described in the Second Acquisition Line Term Loan Note,
the terms, covenants and conditions of which are hereby deemed incorporated
herein by this reference and made a part hereof.

     6.   Third Replacement Revolving Credit Note.  Contemporaneously herewith,
          ---------------------------------------
Borrower shall execute and deliver to Bank its Replacement Revolving Credit Note
in the principal sum of Fifteen Million ($15,000,000.00) Dollars (the "Third
Replacement Revolving Credit Note") to evidence the Obligations with respect to
the loans and advances made or to be made by Bank to or for the benefit of
Borrower under the Revolving Credit (as hereby reduced), all as more fully
described in the Replacement Revolving Credit Note, the terms, covenants and
conditions of which are hereby deemed incorporated herein by this reference and
made a part hereof.  The Third Replacement Revolving Credit Note replaces and
supersedes, but does not extinguish any unpaid Obligations evidenced by or
constitute a novation of, the Third Replacement Revolving Credit Note.

                                       5
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     7.   Conditions Precedent. Bank's obligations under this Amendment are
          --------------------
subject to the following conditions precedent (all instruments, agreements and
documents to be in form and substance satisfactory to Bank and its counsel):

          (a)  Borrower shall duly execute and/or deliver, or cause to be duly
executed and/or delivered, to Bank the following:

               (i)    This Amendment;

               (ii)   The Third Replacement Revolving Credit Note;

               (iii)  The Second Acquisition Line Term Loan Note;

               (iv)   A certified (as of the date of this Amendment) copy of
resolutions of each Obligor's board of directors authorizing the execution,
delivery and performance of this Amendment.

               (v)    A certificate (as of the date of this Amendment) of each
Obligor's corporate secretary as to the incumbency and signatures of the
officers of such Obligor executing this Amendment;

               (vi)   The written opinion of Borrower's and BHL's counsel, dated
the date hereof and addressed to Bank; and

               (vii)  Such other instruments, agreements and documents as Bank
may reasonably require.

          (b)  No Event of Default or Potential Default shall have occurred and
be continuing.

          (c)  In addition to satisfaction of the condition precedent set forth
above, the following shall be conditions precedent to the making of any Loan
under the Acquisition Line Facility (all instruments, agreements and documents
to be in form and substance satisfactory to Bank and its counsel):

               (i)    Borrower shall furnish to Bank a written request for a
Loan under the Acquisition Line Facility, which request shall specify the date
on which Borrower is acquiring Walker for which proceeds of the Loan are being
requested;

               (ii)   Bank's receipt of copies of all instruments, agreements
and documents executed or to be executed and/or delivered and exchanged in
connection with the acquisition of Walker;

               (iii)  UCC, judgment, federal and state tax liens against the
Assets of Walker;

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               (iv)   Bank shall be expressly entitled to rely on any opinion
furnished to Borrower in connection with its acquisition of Walker;

               (v)    In connection with any request by Borrower that Bank make
amortizing Loans under the Acquisition Line Facility pursuant to Paragraph 7 of
the Second Amendment, an orderly liquidation appraisal of any machinery and
equipment being acquired by Borrower conducted by a reputable appraiser selected
by Borrower and reasonably acceptable to Bank;

               (vi)   Evidence of the consummation of the acquisition of Walker
in accordance with all applicable Law and in accordance with all representations
and warranties made to Bank by or on behalf of Borrower in connection with
Borrower's request for a Loan under the Acquisition Line Facility; and

               (vii)  Such other instruments, agreements and documents as Bank
may reasonably require in connection with or to evaluate Borrower's request for
a Loan under the Acquisition Line Facility.

     8.   No Waiver of Defaults. This Amendment is not and shall not be deemed
          ---------------------
to be a waiver of any defaults or Events of Default or Potential Defaults which
may now exist or hereafter occur under the Financing Agreements.

     9.   No Obligation to Extend.  Borrower acknowledges and agrees that,
          -----------------------
notwithstanding anything to the contrary set forth in this Amendment, Bank has
no obligation to further amend the Financing Agreements or otherwise restructure
the indebtedness described in this Amendment, and that neither Bank nor its
representatives have made any agreements with, or commitments or representations
or warranties to, Borrower (either in writing or orally) other than as expressly
stated in this Amendment.  Nothing contained in this Amendment, or any
compliance with the terms of this Amendment or any of the instruments,
agreements or documents referred to in this Amendment, shall impose any
obligation on the part of Bank to consummate a further restructure of the
indebtedness described in this Amendment or provide any further financial or
other accommodation.

     10.  Integrated Agreement.  This Amendment and all of the instruments,
          --------------------
agreements and documents executed and/or delivered or to be executed and/or
delivered in conjunction with this Amendment shall be effective upon the date of
execution hereof and thereof by all parties hereto and thereto, and shall be
deemed incorporated into and made a part of the Financing Agreements.  All such
instruments, agreements and documents, and this Amendment, shall be construed as
integrated and complementary of each other, and as augmenting and not
restricting Bank's rights, remedies, benefits and security.  If, after applying
the foregoing, an inconsistency still exists, the provisions of this Amendment
shall constitute an amendment thereto and shall govern and control.

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<PAGE>

     11.  Expenses of Bank.  Borrower shall pay all expenses (including the
          ----------------
reasonable fees and expenses of legal counsel to Bank) relating to preparation,
negotiation, administration and enforcement of this Amendment and the Financing
Agreements.

     12.  Governing Law.  This Amendment shall be governed by and construed and
          -------------
interpreted in accordance with the laws of the Commonwealth of Pennsylvania.

     13.  Seal. This Amendment is intended to take effect as an instrument under
          ----
seal.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to Loan
and Security Agreement to be duly executed and delivered the day and year first
above written.

Attest:                             BERGER FINANCIAL CORP.,
                                    a Delaware corporation

By: /s/ Theodore A. Schwartz        By: /s/ Joseph F. Weiderman
   -------------------------            ---------------------------------
   Theodore A. Schwartz                 Joseph F. Weiderman,
   Chief Executive Officer              President

        [Corporate Seal]

Attest:                             BERGER BROS COMPANY,
                                    a Pennsylvania corporation

By: /s/ Theodore A. Schwartz        By: /s/ Joseph F. Weiderman
   -------------------------            ---------------------------------
   Theodore A. Schwartz                 Joseph F. Weiderman,
   Chief Executive Officer              President

        [Corporate Seal]

Attest:                             BERGER HOLDINGS, LTD.,
                                    a Pennsylvania corporation


By: /s/ Theodore A. Schwartz        By: /s/ Joseph F. Weiderman
   -------------------------            ---------------------------------
   Theodore A. Schwartz                 Joseph F. Weiderman,
   Chief Executive Officer              President

      [Corporate Seal]

Attest:                             COPPERCRAFT, INC.,
                                    a Texas corporation

By: /s/ Theodore A. Schwartz        By: /s/ Joseph F. Weiderman
   -------------------------            ---------------------------------
   Theodore A. Schwartz                 Joseph F. Weiderman,

                                       8
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   Chief Executive Officer            President

      [Corporate Seal]

Attest:                             WALKER METAL PRODUCTS, INC.,
                                    a Georgia corporation


By: /s/ Theodore A. Schwartz        By: /s/ Joseph F. Weiderman
   -------------------------            ---------------------------------
   Theodore A. Schwartz                 Joseph F. Weiderman,
   Chief Executive Officer              President

       [Corporate Seal]
                                    SUMMIT BANK


                                    By: /s/ Linda Serinese
                                        ---------------------------------
                                        Linda Serinese
                                        Vice President

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